Use of a pilot tone for clock and carrier recovery in mutlicarrier transmission

摘要

A timing and frequency offset estimation method for OFDM uses a pilot tone in calculating timing offset estimation and a frequency offset estimation. The pilot tone includes only one subcarrier and has uniform magnitude and a uniform phase rotation. The estimation algorithm is based on a correlation function. By changing the interval between two samples in correlation, the maximum estimation range for the frequency offset can be extended to ±N/2 subcarrier spacings, where N is the number of total subcarriers. Thus, the frequency synchronization scheme for OFDM systems has a wider range and is simpler than traditional ones which require separate fine and coarse synchronization.